1. Technical Field
The present invention relates to an optical scanner, an image display apparatus, and a head-mount display.
2. Related Art
For example, as an image display apparatus such as a head-mount display, a projector, or the like, an optical scanner that performs 2-dimensional scanning with light may be included.
An optical scanner according to JP-A-2009-75587 includes a frame, an outer driving portion that is suspended to the frame through a first torsion spring and that can rotate about a first axis, an inner driving portion that is suspended to the outer driving portion through a second torsion spring, and that can rotate about a second axis orthogonal to the first axis, and a stage that is arranged on the upper portion of the inner driving portion, and rotates together with the inner driving portion.
In the optical scanner according to JP-A-2009-75587, the outer driving portion is rotated about the first axis, and also the inner driving portion is rotated about the second axis by Lorentz force generated by electric currents that flow through coils provided respectively in the inner driving portion and the outer driving portion and a magnetic field between a pair of magnets arranged on both sides of the frame. Accordingly, scanning is performed by reflecting light on a mirror surface formed on the stage.
Here, the stage is formed in a disk shape, is linked to the inner driving portion through a linking portion protruding so that the center of the stage and the central axis are identical to each other, and is arranged so as to be symmetrical with respect to the first axis and the second axis, respectively, in the plan view.
However, in this optical scanner, light is generally incident in a direction inclined to the mirror surface, and the spot shape of the light in the mirror surface forms an elliptical (oval) shape.
Accordingly, in an optical scanner disclosed in JP-A-2009-75587, there is a problem in that the mirror surface has an unnecessary region that is not used in the light reflection, or a portion of light is not incident on the mirror surface and is wasted.